The invention relates to hydrostatic bearings especially high speed, high pressure hydrostatic bearings.
Hydrostatic bearings can carry relatively large loads, are relatively inexpensive and are relatively efficient. They are also quite accurate in positioning two relatively movable structures if the hydraulic bearing pad between the two relatively movable bearing structures is relatively thin or a bearing cavity seal is closely adjacent the structure to be sealed. A major problem, however, resides in wear and scratching of the harder element of the seal or other mating structural areas. It appears that hard abrasive particles are implanted into the softer of the two mating surface areas and, embedded therein, they lap and grind down the harder of the two surfaces. Even very fine filters such as 10 micron lubricant filters have been found to be ineffective in preventing surface scratching and wear.
It has been tried to use resilient plastics adapted to resiliently receive hard particles so as to prevent scratching of the opposite surfaces. They melted under the heat generated by the bearing structure. A layer of rubber on a cast iron support structure, for example, which has been found to be a good bearing structure for ship propeller shafts that are exposed to cold water, overheated rapidly under given speed, high load conditions.